Arch



Jan. 15, 1924. 1,480,882

L. DAVIDSON ARCH Filed June 2 1921 Z mfNToR LOUIS DAVIDSON, OF NEW YORK, N. Y.

, ARCH.

Application filed June 2,

To all whom it may concern:

Be it known that I, LOUIS DAVIDSON, a citizen of the United States of America, residing in the borough of Manhattan, city, county, and State of New York, have invented certain new and useful Arches Especially Useful for Carrying Light Loads Over Long Spans, of which the following is a specification.

My invention relates to improvements in arch construction, and its object is to eliminate the expensive shop and field work incidental to fabricating and constructing arches, and to substitute standardized parts of extremely simple design and construction, so that all the work could be done successfully by unskilled labor, instead of the customary high priced mechanics and artisans now employed.

Two embodiments of the invention are illustrated in the accompanying drawing in which- Fig. 1 is an elevation of a roof arch, and does not show the roofing.

Fig. 2 is a plan view of shoe 1 shown in Fig. 1, and drawn larger, for a steel segment arch;

Fig. 3 is an elevation of Fig. 2 and shows the roof sheathing in addition;

Fig. 4 is a transverse section of Fig. 3 on line 4-4;

Fig. 5 is an elevation of shoe 1 shown in Fig. 1 for a timber segment arch, and also shows the sheathing.

Fig. 6 is a transverse section of Fig. 5 on line 66.

Similar numerals refer to similar parts throughout the several views. 1

The connecting shoe is marked 1, and is preferably a steel casting into which arch segments 2 are placed. The shoes 1 are formed with relatively deep sockets 1*, en-

tirely closed in cross section, and the ends of the segment 2 are adapted to snugly fit into said sockets. These shoes therefore act to firmly connect the adjacent ends of two segments together, and therefore sustain any distortion stresses which may be transmitted from one segment to another. 3 is the tie rod to resist the horizontal thrust of the arch. 4 is a tie rod for the purpose of resisting distortion due to unsymmetrical loading on the arch, and thereby prevent bending and tensile stresses from being introduced .in the arch. 5 is a rod hanger and serves to prevent the horizontal tie rod 3 1921. Serial No. 474,505.

from sagging. 6 is a perforated lug onto which rods 4 connect. 7 are beams to support the roof between the arches and deliver the loads to them. 8 is the roof sheathing and roofing supports. 9 is a lug on shoe 1 for the purpose of connecting the shoe to beam 7. 10 is a seat support for beam 7. 11 are conventional turn-buckles. 12 is the diaphragm in shoe 1, against which arch segments 2 beer.

When the resistance line of an arch comes within its middle third, or takes the form of a parabola, it is supposed to be in compression throughout, except when it is load ed unsymmetrically. While my arch can be designed within these lines, it is not limited thereto, and its scope is general.

Shoes 1 are made long and strong enough to resist bending in the arch, and take the place of riveted or other rigid connections.

In most cases it will be advisable to introduce tie rods 4 to prevent bending, and reduce the shoe length. But my arch is efleotive with or without the tie rods 4.

Ties 4 can also be used effectively on an ordinary rigidly constructed arch.

In order to avoid expensive bevel cuts on the arch segments, the diaphragm faces 12 are cast on a bevel so that the faces of the diaphragm are perpendicular to the direction of the arch segments. This makes it practical to use mill cut lengths of steel as delivered, without shop work on the ends. If the arch ribs are to be of timber, then the ends are to have right angle cuts, and the bevels which are expensive and uncertain are dispensed with. The ends of the arch segments or beams bear against the dia phragm 12, and the end thrust of two adjoining beams or segments is transmitted substantially directly from one beam or segment to the next, the diaphragm 12 being in simple compression, and relieving the shoes of substantially all strains except the distortion strains. Moreover, the structure conforms to theoretical requirement inasmuch as the compression stress of one segment or beam is transmitted to the next beam or segment at a point which is common to the two beams, or substantially so, and not located in space.

The results accomplished by my arch invention, are 1st that the arch is delivered to the site as a series of plain members called segments, and require no riveting or bolting to erect, and no shop work. 2nd the archv can be erected in a minimum amount of time. 3rd my arch permits the maximum amount of light and air to circulate. 4th saves materials. 5th the arches can be dismantled without injuring the materials and therefore used again efiiciently.

Shoe 1 can be cast or built up, and can be made a number of different shapes instead of the square section shown in my drawing, and various materials and shapes can be employed for the segments.

The part against which the ends of the segments abut in the sockets is not limited to the form shown in the drawings, but may have other forms than that of the diaphragm 12 shown.

My invention is useful where ordinary arches and trusses are employed, and also for supporting false work in long span masonry and concrete construction. It is especially useful in times of war as it pro-v vides a bridge frame which is portable in small light units and can be erected and dismantled in a minimum of time, as it requires no bolting or riveting.

It is also ve useful where it is desired to create architectural effects over long spans, especially of a temporary character, as spanning streets with electric lights.

An arch according to the present invention may be used in trussed arches and in arched trusses where these latter include as a main element a curved upper chord.

If the arch is built on firm supports, the horizontal tie rod is unnecessary.

It is evident from the several figures shown that man modifications can be made, and I do not intend to be understood as limiting myself to the outlines and shapes shown in the drawing. The'essential principles of my invention as illustrated in the accompanying drawing may be varied with in the limits of the appended claims.

I claim as my invention 1. An arch or truss having a general curvilinear shaped upper chord comprising segments and shoes, sockets entirely closed in any cross section thereof in said shoes into which the ends of said segments or beams are adapted to be inserted, 'means whereby the compression load is transmitted from the end face of one segment to the end face of another without stressing the outer walls of the shoes, said sockets having connected walls for sustaining distortion strains in vertical and horizontal planes.

2. An arch or truss having a general curvilinear shaped upper chord comprising segments and shoes, sockets entirel closed in any cross section thereof in said shoes into which the ends of said segments or beams are adapted to be inserted. said sockets having a partition or diaphragm therein against which the end faces of said sagments are adapted to bear whereby the compression load is transmitted from the end face of one segment to the end face of another, said sockets having connected walls for sustaining distortion strains in vertical and horizontal planes.

3. An arch or truss having a general curvilinear shaped upper chord comprising segments and shoes, sockets entirely closed in any cross section thereof in said shoes into which the ends of said segments or beams are adapted to be inserted, said sockets having a partition or diaphragm therein against which the end faces of said segments are adapted to bear whereby the compression load is transmitted from the end face of one segment to the end face of another, said sockets having connected walls for sustaining distortion strains in vertical and horizontal planes, said segments having squared ends, said partition having faces at an angle corresponding to the angle between the end faces of two segments in said shoes.

4. An arch or truss having a general curvilinear shaped upper chord comprisin segments and shoes, sockets entirely closec l in any cross-section thereof in said shoes into which the ends of said segments or beams are adapted to be inserted, means whereby the compression load is transmitted from the end face of one segment to the end face of another without stressing the outer walls of the shoes, said sockets having connected walls for sustaining distortion strains in vertical and horizontal planes, and tension rods connecting the ends of the arch and its crown.

5. An arch or truss shoe having sockets therein entirely closed in any cross-section thereof into which the ends of segments may fit, means in the shoe which permit of the compression strains being transmitted from an end face of one segment to the end face of another without stressing the outer walls of the shoe, said sockets having connected walls for sustaining the vertical and horizontal distortion strains which may be transmitted thereto by the ends of said segments.

6. Anv arch or truss shoe having sockets therein entirely closed in any cross-section thereof into which the ends of segments may fit, means comprising a partition in said shoe, which permit of the compression strains being transmitted from an end face of one segment to the end face of another without stressing the outer walls of the shoe, said sockets having connected walls for sustaining the vertical and horizontal distortion strains which may be transmitted thereto by the ends of said segments.

7. An arch or truss shoe having sockets therein entirely closed in any cross-section thereof into which the ends of segments may fit, means in the shoe which permit of the compression strains being transmitted from an end face of one segment to the end face of another without stressing the outer walls of the shoes, said sockets having connected walls for sustaining the vertical and horizontal distortion strains which may be transmitted thereto by the ends of said segments and lugs projecting from the body of sai shoe for connecting to transverse beams, and

' lugs on the underside of the shoe for connecting web members.

8. An arch or truss shoe, having socket pieces for receiving the ends of beams, said socket pieces being entirely closed in any cross-section thereof and having walls for sustaining the vertical and horizontal strains which may be transmitted thereto by'the ends of said inserted beams, and means in said socket-pieces for sustaining the end thrust or longitudinal strain of said beams,

and means on the sides of said shoe for fastening the ends of beams connecting two arches.

9. An arch or truss havin a genleral curvilinear shaped upper chor comprisin segments and shoes, sockets entirely closes in any cross-section thereof in said shoes into which the ends of said segments or beams are ada ted to be inserted, and means in said shoes or transmitting the compression load from the end face of one segment to the end face of another, said means being substantially in the middle of the shoes, and said sockets extendin substantially to said middle, and said soc ets having connected walls for sustaining distortion strains in vertical and horizontal planes.

LOUIS DAVIDSON. 

